1. Field of the Invention
The present invention relates to a scalable video coding (SVC) scheme in digital broadcasting, and more particularly to a method for stably transmitting a high-definition image by utilizing redundant resources in a wireless transmission environment.
2. Description of the Related Art
In general, wireless transmission of digital video streams is performed by using a limited resource (i.e. bandwidth). For such wireless transmission, a bursty environment is likely to cause a loss of transmitted data and is thus a factor that should be overcome.
FIG. 1 is a block diagram illustrating a conventional transmission environment for a digital video stream.
The conventional transmission environment for a digital video stream includes an encoder 11 for encoding and transmitting a high-definition digital video stream, a bursty wireless transmission medium 100 for transmitting a high-definition video stream, and a decoder 12 for receiving and decoding received high-definition digital video stream. Although the details of a transmission device and a reception device are not shown in FIG. 1, the constructions of these devices is well known to those skilled in the art and need not be discussed herein.
The term “bursty wireless environment” means a wireless environment in which data may momentarily crowd together. Such a bursty wireless environment may cause a burst error representing a loss of unspecified data. Such a burst error is an important consideration factor for multimedia data in which continuity of data is very important.
In order to transmit a high-definition digital video stream, which is related to the present invention, in such a bursty wireless environment, characteristics or features such as a wide bandwidth to ensure a high bit rate and error recovery for lost data, which may be caused in the bursty error environment must be provided.
With respect to the wide bandwidth to ensure a high bit rate, various compression methods have been proposed in order to overcome limited bandwidth resources. However, there is a limitation in ensuring bandwidths by such compression methods. Therefore, it is necessary to develop a method capable of more efficiently allocating and ensuring bandwidths.
With respect to error recovery, various methods, such as a re-transmission method, an interleaving method, a forward error correction (FEC) method, etc., have been applied. However, such applications are problematic in that they cannot always treat (heal; overcome; solve) an error. It is difficult to instantly predict the network environment and is thus difficult to predict an occurrence of error in the bursty wireless environment, and because it is necessary to install a large-capacity buffer at a terminal of the system in order to process images without interruption when a video stream having a high bit rate is transmitted.